Since a gene is just a molecule, it can’t choose to maximize its fitness, but evolution makes it seem as though it had.… Why, for example, do songbirds sing in the early spring? The proximate cause is long and difficult. This molecule knocked against that molecule. This chemical reaction is catalyzed by that enzyme. But the ultimate cause is that birds are signalling territorial claims to each other in order to avoid unnecessary conflict. They just do what they do. But the net effect of an immensely complicated evolutionary process is that songbirds behave as though they had rationally chosen to maximize their fitness.
Laboratory experiments on pigeons show that they sometimes honor various consistency requirements of rational choice theory better than humans (Kagel, Battalio, and Green 1995). We don’t know the proximate explanation. Who knows what goes on inside the mind of a pigeon? Who knows what goes on in the minds of stockbrokers for that matter? -- Ken Binmore, Rational Decisions
Nic_Smith comments on Rationality quotes: April 2010